Retired Army Col. John Alexander, 74-year-old former Green Beret A-Team commander and developer of weapons at Los Alamos, N.M., says UFO disclosure has already occurred, and that the ultimate solution to UFOs is more complex than most people think.

Alexander quotes President Harry Truman: "I can assure you the flying saucers, given that they exist, are not constructed by any power on Earth."

"Disclosure has happened," Alexander told AOL News. "It starts with former presidents Truman, Carter, Reagan and [the Soviet Union's] Gorbachev. I've got stacks of generals, including Soviet generals, who've come out and said UFOs are real. My point is, how many times do senior officials need to come forward and say this is real?"

"At one time, before a lot of this information was released, I could see both the classified and the unclassified material. And I will tell you that 98 percent of the information was already in the public domain. The only things that weren't there was stuff like sources and method, which is protected, but the information about the incident was already out there."

Several months ago, a group of ex-military officers came forward to discuss their experiences when UFOs reportedly tampered with American nuclear missile sites. While Alexander acknowledges the events, he suggests why there was no intense intelligence investigation of these incidents.

"They absolutely happened, but when it's a one-time event, the attitude of investigators is: If it happens again, we'll get nervous, but since it didn't happen, put it aside.

"It's sort of an indictment that says, despite overwhelming evidence of interaction with strategic systems, nothing was done. And in my view, it is put, like a number of things, in the too-tough-to-handle bin."

In his new book, "UFOs: Myths, Conspiracies and Realities," Alexander writes, "UFOs are real! With no prevarication or qualification of terms, there are physical objects of unknown origin that do transit our universe. The evidence that supports those statements is simply overwhelming."

The evidence he speaks of includes the hard data of sensor technology that has frequently confirmed the reality of physical craft and the high quality of extremely reliable eyewitnesses who are "neither misreporting facts nor delusional."

"The problem is, when you discuss UFOs, we are talking everything from little balls of light to hard craft a mile or more across, and everything in between. So what is it?" Alexander asked."I argue that, not only are we not solving the problems yet, we're not even asking the right questions, because we approach this wrong. I suspect that consciousness is a piece of the puzzle. We talk about UFOs, saying it's a technology that's 1,000 years in advance, but it really isn't. If you follow the history of these things, usually it is somewhat in advance, but not beyond our comprehension by any stretch of the imagination.

"The conundrum you get into is, yes, they are seen by sensors; however, at other times, they are not seen by sensors that should've seen them, and that's one I can't answer."